The present disclosure relates to a multilayer electronic component, a manufacturing method thereof, and a board having the same mounted thereon. Unless otherwise indicated herein, the materials described in this section are not prior art to the claims herein and are not admitted to be prior art by inclusion in this section.
Among electronic components, inductors, important passive devices configuring electronic circuits, together with resistors and capacitors, are used as components for removing noise, used as components configuring LC resonance circuits, and the like.
Passive devices such as power inductors, and the like, used in smartphones, portable communications devices, and the like, are used in a high frequency band of 1 MHz or more. Therefore, a soft magnetic material prepared by mixing, grinding and calcining a plurality of metal oxides, for example, soft magnetic ferrites, Fe2O3, NiO, CuO, ZnO, and the like, can be used.
However, as amounts of data transmitted by smartphones, portable communications devices, and the like, have significantly increased, Central Processing Unit (CPU) switching frequencies have also been increased to allow for high-speed data processing, and accordingly, power usage in mobile devices, and the like, has rapidly increased due to the implementation of large screen sizes and high degrees of resolution in portable communications devices and smartphone screens. Due to the increase in the power usage amount in mobile devices, as described above, passive devices such as power inductors, and the like, disposed within and used in plural in driving circuit designs for devices such as CPUs, display devices, power management modules, and the like, should have high power consumption efficiency characteristics.
In order to improve the efficiency of power inductors, or the like, a power inductor device capable of being used within a high frequency band of 1 MHz or more by replacing a soft magnetic ferrite material with a fine metal powder and of having improved energy consumption efficiency and direct current (DC) bias characteristics through significantly decreased eddy current loss therein, has been produced.
Japanese Patent Laid-Open Publication No. 2007-027354 appears to disclose a thin film inductor or a wound inductor in which a metal powder is used in the manufacturing of the inductor.
Such a thin film inductor may be manufactured through a process in which a coil shape is formed on a board such as a printed circuit board (PCB), or the like, using a plating method, a metal-epoxy mixed material obtained by mixing metal powder and an epoxy resin with each other is used to enclose the formed coil shape through press-molding, and the epoxy resin is cured in a heat treatment.
A wound inductor may be manufactured by winding a copper wire, enclosing the wound copper wire with a metal-epoxy mixed material obtained by mixing metal powder and an epoxy resin with each other, press-molding the enclosed copper wire in a mold at high pressure to implement a chip, and then curing the epoxy resin in a heat treatment.
Inductors manufactured using the methods as described above have significantly excellent DC bias characteristics as compared to ferrite multilayer inductors, and as a result, the efficiency of power management integrated circuit (PMIC) module sets, and the like, may be improved by an amount of several percent or more.
As described above, a magnetic metal multilayer inductor has been studied in order to simultaneously secure mass production, in addition to advantages in which DC bias characteristics and efficiency characteristics of the inductor, or the like, are improved due to the application of a soft metal powder. The magnetic metal multilayer inductor may be manufactured by forming a uniform mixture of metal powder and a polymer as a sheet instead of an oxide ferrite sheet, and performing a series of processes such as a cutting process, a via hole punching process, an internal conductor printing process, a stacking process, a sintering process, and the like, on the magnetic metal sheet.
In such a magnetic metal multilayer inductor, DC bias characteristics may be implemented on a level similar to that of the thin film inductor or the wound inductor, but a quality factor (Q) value affecting efficiency characteristics of the inductor is further required to increase, and direct current (DC) resistance (Rdc) is required to decrease.
As for efficiency characteristics, core loss of a magnetic material is dominant in a low current region, and an influence of resistance on an internal coil is dominant in a high current region. Particularly, in order to increase inductor efficiency in low current conditions, directly associated with standby power usage time, a magnetic material having low core loss of a magnetic metallic material and high magnetic permeability should be applied.